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12.17
The common components of cells
 
  Let us look at the common components of all cells. On the next few pages are three diagrammatic representations of the 3 broad categories of cells:  
 
(1) mono-cellular cells ( prokaryota)
(2) multi-cellular plant cells (eukaryota)
(3) multi-cellular animal cells ( eukaryota)
 
12.9.1 Using a graphic style to make it easier to understand the common and unique components of cells  
  To make it easier to understand the common and unique components of cells, we use a simplified graphic style of using circles to represent cell boundaries. Of course, no cell is a perfect sphere.  
  If you have even seen pictures of cells taken via electron microscopes then you will know cells come in all different shapes and sizes. In fact, no two cells can be described as perfectly alike- every cell, just as every living thing is unique to some degree.  
  This simple yet profound understanding is completely consistent with UCA. However, UCA also allows us to see and understand more clearly the universe of cells via simplified models.  
12.9.2 Prokaryote cells (bacteria)  
   
12.9.2 Eukaryote cells (plants)  
   
12.9.3 Eukaryote cells (animals)  
   
12.9.4 Summary of cells types  
 
Attribute Prokaryote Eukaryote
Plant Animal
Cell Walls 4 2 1
Temp 200 C 100C 50C
Layer DNA 6 4 3
Tubulin Dimers 0 1 1
Centriole 0 0 1
Chloroplasts 0 0
Mitochondria 0
 
12.9.5 The common components of all cells  
  From the diagrammatic representation of the three broad categories of all cells in the universe, you will see they share common characteristics- they all have boundaries, they all have the ability to create weak chemical fusion ( protein manufacture via ribosome's). They all contain chemical memory (DNA).  
  In other words, all cells solve problem 1 and 2 we mentioned earlier.  
  From the diagrammatic representations, we can also see that plant and animal cells share closer similarities than animal to bacteria cells (for example). Both plant and animal cells have internal strong chemical fission/fusion engines (solving problem no #3), a common language (solving problem no#4) and specialized co-dependence (solving problem no#5).  
12.9.6 The cell boundary  
  All cells have boundaries of various thickness and layers. The thickness and layering provides the advantage of isolating the "inner world" of the cell from the dangerous and unpredictable "outer world". For a mono-cell ( Diagram A), the prototype cell- he world is highly unpredictable and dangerous. So its boundary is for maximum survival at the cost of being a part of a larger whole.  
  Proto-bacteria can survive in temperatures up to 200C and less than -10C. The heater the temperatures, the better. This is because mono-cells are dependent on external conditions of strong chemical fusion/fission- they don't have internal engines.  
  That is why Bacteria is more dangerous at the extremes of temperatures- extreme het and extreme col- infection - fever and frostbite. It is also why temperature based disinfections ( especially water/steam based) is substantially less effective than gas blast/vacuum extraction- neutralizing water based/air based bacteria.  
  At the other end, animal cells have only thin membranes ( except for some specialized cells such as skin). which allows higher interconnection and communication, but leaves these cells extremely vulnerable to attack and changes in external conditions. Importantly, ( as we will discuss in more detail in a moment), the thin membrane and fluid structure of animal cells enables almost spontaneous shape change- changing shape quickly and flexibly is critical for independent movement.  
  Instead of thriving at the margins (het and col), animal cells thrive at the optimum cellular community mean ( usually somewhere between -20C and 40C). The closer the external environment is to the mean, the better the performance of cells within the complex cellular community at operation. For humans, that figure is an air temperature of around 23C.  
  That is why health is optimum or more rapidly repaired when external conditions allow a skin temperature of around 23C. In contrast, bacteria attacking a human being, requires conditions towards the extreme- high temperatures for multiplication ( tending to crowd mitochondria and cause an over production of energy) only to deplete the body and cause extreme col, to depress the immune system.  
12.9.7 The cytoskeleton
  The cytoskeleton of all heterotroph species cells is the essential structure for survival. Like many structures it is multi-purpose:  
 
o Maintains the boundaries of the cell
o Opens and shuts in specific ways to allow the important and export of substances, including replication;
o The outer layer behaves as either tens of thousands of tiny limbs, or has a huge tail that "whips" the cell into its desired position;
o Is the basis of communication storage and control between what happens in the cell and what is happening with the outside world ( i.e. other cells and the organism as a whole). What we mean is that to a cell, its brain is its structure, not the nucleus.
 
  i## We note that this is completely contradictory with contemporary scientific view of the nucleus = brain = centre of intelligence of a cell. However, we say and will prove the argument that the skeleton of a cell is its centre of intelligence, not the nucleus. We will show that the nucleus is actually the sexual organs and hard coded "library" of the cell, not its centre of intelligence.  
  The cytoskeleton of cells are quite sophisticated and "in touch" with what is happening and where things are. The cytoskeleton in many cells should be viewed as having a good common sense intelligence. The specific features of the cytoskeleton of a cell are:  
  Cell membrane  
  The cell is separated from its surroundings by a very thin sheet-like outer boundary, the cell membrane (sometimes called the plasma membrane). The membrane itself is made from fats connected to sugars (including Potassium) forming a water attractive and water repulsive boundary.  
  Cell membranes themselves can be a specific "higher purpose" function of a cell such as hair, nails and skin. These cells live longer, have less sex (i.e. replicate slower) and because they have such hard cell membranes, live more economized lives. Liver cells on the other hand are large mass factories, with super soft cell membranes and vast spaces for large particles to come through and be broken down, new components to be added to an organisms fuel supply network.  
  Cytoplasm  
  The cytoplasm is the general liquid that is contained within the walls of the cell. All the components of the cell are contained within this liquid base. In animals, this cytoplasm is generally maintained in a relatively neutral state.  
  Cilia (singular Cilium)  
  These are fine hairlike projections that extend from the surface. These beat rhythmically from side to side in living tissue. Their beating moves the cell along, or if the cell is anchored can move what is in front of them along ( e.g. the cells of lungs of a animal).  
  Flagellum (plural Flagella)  
  Some animal cells have a single whip like structure extending from part of the cell surface. By means of thrashing movements, a flagellum can move fluids along a tube within the body of the cell. Flagella that extend from the cells on the outside of some organisms can assist in movement of the cell itself.  
  Centriole  
  Traditionally, the Centriole is not considered part of the cytoskeleton. However as we shall see, it shares similar structural components to the other major parts of the cytoskeleton.  
  A Centriole consist of an outer membrane, protecting a completely neutral water pool (i.e. no impurities, no water ions, just pure and safe) in which float structures called microtubules. Microtubules in turn are made up of a particular protein called Tubulin Dimers. Tubulin Dimers are made up of 450 amino acids. Tubulin Dimers in microtubules are in pairs and have the important and consistent behaviour of switching "a" position or "b" position depending on the presence and position of electrons within its protein structure. Tubulin Dimers create specific patterns of structure in all cells of 13 columns to each microtubule.  
  Microtubules are hollow inside and this space is always filled with pure neutral water ( i.e. no water ions are present.) The inner surface of Tubulin Dimers are therefore very sensitive to any change in electron status as even a small electron shift could mean a shift of these inner Tubulin Dimers to only one of two positions ( e.g. 0 or 1).  
  Microtubules themselves are usually arranged in a "fan" like structures of either triplets or duplets of 9 to make 2 larger groups of tubes in a centriole. During replication of a cell, these structures replicate one another.  
  Microtubules can vary dramatically in length, such as in neuron cells and nerve cells in the body ( sometimes centimetres in length!). On average there is around 13 x 8 tubulin dimers per microtubule, making an average of around 4000 tubulin dimers per Centriole of an average cell.  
  A further feature of microtubules in bundles is that they create protein bridges between one another called MAPS (microtubule associated proteins). These are direct bridges and can be numerous or few. An average for "parallel processing capacity for microtubules is around 200 to 600.  
  Microtubules are also found in the filamentous cytoskeleton as well as endoplasmic reticulum ( both of which we will discuss in a moment).  
  In terms of performance, bundles of microtubules can change from individual sequence of 0's and 1's (different positions because of electrons) due to the specific change in electron less than one millionth of a second (as microtubules are very small and electrons are very fast).  
  Centrioles are usually always found at the centre of the cell, regardless of whether the nucleus changes position or not.  
  Filamentous cytoskeleton  
  These are long tube like structures throughout the cell. These branch out to the cell membrane and to other components of the cell such as ribosome's and endoplasmic reticulum ( which we will discuss in a moment).  
  Filamentous cytoskeleton's are principally made up of hard cased microtubules with the capacity to carry larger molecules along its surface.  
  Importantly, in animal cells, Filamentous cytoskeleton always seems to position or reposition (after a required shift of cell components) themselves at 90 to the cell wall ( cell membrane) and the Centrioles. There can be a substantially larger number of Tubulin Dimer in Filamentous cytoskeleton's ( up to 60,000! in just one filamentous cytoskeleton) also with MAP connections.  
  Endoplasmic reticulum  
  Throughout the cytoplasm are long, thin "worm-like" membrane structures called endoplasmic reticulum. These are essentially hard cased microtubules with longer MAPS that behave by thrashing about, allowing the endoplasmic reticulum to have independent movement, regardless of the changing structure of the cell walls.  
  These endoplasmic reticulum vary in size, shape and locality ( i.e. some "large" ones move in and around the nucleus, while others move around the other structures ( e.g. storage depots, factories). Depending on size, Endoplasmic reticulum can contain up to 50,000 Tubulin proteins arranged in microtubules.  
  Contrary to popular science, it is the endoplasmic reticulum using ribosome chains (long chains of amino acids, enzymes and bases i.e."ready made" platforms) on which new DNA (called RNA) is created. During the process of cell replication, Endoplasmic reticulum move long chains of ribosome's into position to match up the uncoiled strands of DNA.  
  Why aren't the components of the cytoskeleton hard and more defined?  
  An essential ingredient to survival is flexibility. To a cell, it is constant modifications to its size, position, operation in relation to the rest of the organism and its own resources to survive. A rigid cell wall and skeleton, would make it impossible for cells to quickly replicate, or for cells to quickly process food or discharge waste. Cells are initially designed to be as fast and as efficient as their specific purpose allows. With the exception of cells that have the specific job of actually being an organisms skeleton, the remaining cells need to be flexible at all times to function properly.  
12.9.8 The fuel stores of the cell  
  Given the multi-purpose brilliance of the cytoskeleton, it probably won't surprise you to see that cells maintain specific store houses for both (a) emergencies (b) maintenance (c) the specific jobs they are supposed to do and (d) for giving birth to replications of Lysomes  
12.9.9 The "stomach" of cells
  In larger organisms, we recognize the stomach as a place where food is digested into smaller parts than are then refined even further. A cell has an equivalent element- called a vacuole. A vacuole is a membrane pool of acids and chemicals capable of breaking down structures- such as proteins into smaller components. A cell may have more than one vacuole. Often vacuole's are considered more as "store houses" rather than active regions of chemical processing.  
12.9.10 Weak chemical Factories of the cells  
  The factories of the cells are principally the Golgi apparatus that manufacture and process all kinds of structures and Ribosome's, principally responsible for all protein production (from mRNA)  
  Ribosome's are powerful protein factories that are unleashed by being dropped into position by endoplasmic reticulum over exposed mRNA (messenger RNA) and begin producing proteins by reading the codes from the DNA (to be discussed further in a moment).  
  Without the right introductory sequence of releasing ribosome's, they are largely inert and so are often stored in separate strands in available space around the cell. Endoplasmic reticulum almost always have ribosome's attached wherever they are moving.  
12.9.11 The nucleus  
  The nucleus is the large membrane enclosed pool in which the chromosomes (specific bundles of nucleic acids are housed). This is the hardwired memory bank and general program library of the cell. It is almost always surrounded by endoplasmic reticulum, which are hyperactive at the time of cell replication.  
  Chromosomes are essentially the bundled pairs of DNA. They are bundled up during the normal working of the cell because the programming code listing the function of the cell is already in operation ( i.e. the cell is functioning and producing what needs to be produced). However at cell replication stage, the endoplasmic reticulum around the nucleus change the ionic nature of the fluid and cause the Chromosomes to unwind and to split.  
  At this point it is the endoplasmic reticulum, in conjunction with the rest of the cytoskeleton that reads the DNA- uploads the next program, replicates the DNA and cell structures, with one exception- the memory sequence for the last program run is added to the DNA strand, not the original DNA strand. This is because in order to read the program- a chemical program- the original copy of that sequence within the DNA had to be destroyed.  
  It is this gap in DNA that allows cells to know where they are up to. In other words, if DNA was complete, then the life of a cell- indeed its destiny would be written. For the purpose of the cell is not just to read programs but to write its experience and pass it on to the next cell and therefore the next generation of that larger species of organism.  
  Why put the nucleus last in the list, not first?  
  We deliberately put the hard wire memory bank, blueprints and library of programs (DNA) last because, since the 1960's it has almost always been listed first.  
  Simply, the nucleus is not critical to the survival of a cell. It is critical to the survival of a species of cell and therefore the species of a more complex organism ( e.g. a human). There is a distinct difference.  
  The nucleus is not the central "brain" of a cell, as we have discussed. Nor are the chromosomes actively disturbed during the normal day to day operation of the cell.  
  This does not diminish the significance or importance of DNA ( as we will soon discuss). It simply puts DNA in the correct perspective as an important an innovative component of an overall intelligent organism with multiple but clearly defined objectives.  
     
 
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